• Buy me a beer
  • Introduction
    • 0.0.1 Warning
    • 0.1 Layout reference
      • 0.1.1 Highlight:
      • 0.1.2 Examples:
      • 0.1.3 Extra info:
      • 0.1.4 External links
    • 0.2 Copyright and permissions
  • 1 Weather
    • 1.1 Weather forecasts
      • 1.1.1 Sources of forecasts
      • 1.1.2 Understanding forecasts
    • 1.2 Wind
      • 1.2.1 Wind strength
      • 1.2.2 Effects of land on wind
      • 1.2.3 Sea and land breezes
      • 1.2.4 Anabatic and katabatic winds
      • 1.2.5 Wind, waves and tide
      • 1.2.6 Accounting for wind
    • 1.3 Other considerations
      • 1.3.1 Visibility
      • 1.3.2 Fog
      • 1.3.3 Thunderstorms
      • 1.3.4 River levels
    • 1.4 Synoptic charts
      • 1.4.1 Isobars and wind
      • 1.4.2 Low pressure
      • 1.4.3 High pressure
    • 1.5 Some meteorology
      • 1.5.1 Air masses
      • 1.5.2 Global circulation
      • 1.5.3 Depressions
      • 1.5.4 Depressions in practice
    • 1.6 Environmental clues
      • 1.6.1 Wind direction
      • 1.6.2 Clouds
    • 1.7 Maritime forecasts
    • 1.8 Weather and trip planning
      • 1.8.1 Deciding where, and if, to go
      • 1.8.2 Checking actual conditions
  • 2 Tides
    • 2.1 Introducing tides
      • 2.1.1 The moon
      • 2.1.2 The Sun - neaps and springs
      • 2.1.3 Meteorological effects
    • 2.2 Tide tables
    • 2.3 Predicting high and low water
    • 2.4 Tidal range
    • 2.5 Tidal streams
    • 2.6 Behavior of tidal streams
      • 2.6.1 Races and overfalls
    • 2.7 Tidal diamonds
    • 2.8 Tidal stream atlases
    • 2.9 Pilots and guidebooks
    • 2.10 Predicting speeds of tidal streams
    • 2.11 Variation of flow through the tidal cycle
      • 2.11.1 50/90 rule
      • 2.11.2 Rule of thirds
    • 2.12 Formal navigation for short crossings
  • 3 Surf and Swell
    • 3.0.1 The life story of a wave
    • 3.0.2 Terminology
    • 3.1 Wind waves
      • 3.1.1 Wind forming waves
      • 3.1.2 Fetch
      • 3.1.3 Time to drop off
    • 3.2 Ground swell
      • 3.2.1 What is swell?
      • 3.2.2 Swell propagation
      • 3.2.3 Sets
    • 3.3 Waves and topography
      • 3.3.1 Waves in shallow water
      • 3.3.2 Refraction and focusing
      • 3.3.3 Diffraction
      • 3.3.4 Reflection
      • 3.3.5 Reefs and boomers
    • 3.4 Wind, waves and tidal streams
      • 3.4.1 Wind and waves against tide
    • 3.5 Surf
      • 3.5.1 Waves and beaches
      • 3.5.2 Surf height
      • 3.5.3 Surf zone features
    • 3.6 Swell and surf forecasts
  • 4 Navigation
    • 4.1 Maps and Charts
      • 4.1.1 Comparing maps and charts
      • 4.1.2 Which to use?
      • 4.1.3 Obtaining maps and charts
    • 4.2 Specifying position
    • 4.3 Latitude and longitude
    • 4.4 The units of the sea
      • 4.4.1 Distances and speeds
    • 4.5 The compass
    • 4.6 Reading charts
    • 4.7 Navigational marks
    • 4.8 Practicalities
      • 4.8.1 On the water
      • 4.8.2 On dry land
    • 4.9 Coastal pilotage
      • 4.9.1 Distance, speed and time
      • 4.9.2 Dead reckoning
      • 4.9.3 Compass use for coastal pilotage
    • 4.10 Signs of tidal flow
    • 4.11 Transits
    • 4.12 Fixes
    • 4.13 Low visibility navigation
      • 4.13.1 Short legs
      • 4.13.2 Aiming off
      • 4.13.3 Attack points
  • 5 Open water navigation
    • 5.1 Chartwork
      • 5.1.1 Measuring bearings
      • 5.1.2 Marking vectors
    • 5.2 Long crossings
      • 5.2.1 Option1: Multiple 1 hour vectors
      • 5.2.2 Option 2: Vectors over several hours
      • 5.2.3 Introduction to multiple hour vector method
    • 5.3 Choosing when to make the crossing
    • 5.4 Finding tidal stream data for long crossings
    • 5.5 Plotting tidal streams
    • 5.6 Finding the course to steer
    • 5.7 Determining estimated positions
    • 5.8 Navigating in open water
      • 5.8.1 Dead reckoning
      • 5.8.2 Fixes and cross bearings
      • 5.8.3 Distance off
      • 5.8.4 GPS

Notes on Sea Kayak Navigation and Tidal Planning

Chapter 4 Navigation

Maps and charts are the main tools that we use in navigation, so it makes sense to take a look at these first. We’ll look at the differences between maps and nautical charts and learn how to specify our position on each. Whilst we’re looking at maps and charts, it makes sense to also introduce the compass. Charts are less familiar to many people, so we’ll take a quick look at how to read a chart, and look at the buoys that are often shown on charts. Finally, we’ll think about the practicalities of using maps and charts both on and off the water.